Packages with hinged closures of fliptop type are widely used in commerce for various purposes, each application having specific needs of easy handling and safety.
The principal factors to be considered in safety closures of fliptop type are resistance to unauthorized opening and resistance to an undesired, accidental opening.
Certain closures are known, considered to be child-resistant, which involve various pieces, camouflage, and movements that are so complex that their opening requires a high degree of specialization, not consistent with the average user, and undesirable in emergency situations.
The hinged fliptop closures of the prior art have inconveniences as to their handling and/or production cost.
The design of hinged closures with locks is already part of the prior art.
In the known designs there are some which present the lock projecting from the lid with the locking effectuated on the cap, or designed as an integral part of the cap with the locking at the lid.
The known closures have complicated designs, with double walls, being difficult to handle and with an elevated cost of raw material.
In some known fliptop closures with the lock designed as an integral part of the cap, the locking occurs internally, in the top of the lid, while the lock is released by applying pressure in an outer region corresponding to the location of the tip of the lock.
Since the lock is hidden on the cap, this design has the inconvenience of its opening not being intuitive, requiring an indication of the location to be pressed upon, in addition to requiring a design with double wall to avoid contact of the lock with the contents of the container.
In another type of known design, the lock is external to the cap and engages with a flange at the edge of the lid to snap in place. This closure presents the inconvenience of being hard to handle, being unlocked by the user's fingernail, and on the other hand it does not offer safety against accidental opening which might occur as a result of any slight deformation of the body of the lid or the cap.
A specific situation in which the deformation of the closure of the container might occur and accidentally release the contents is the transporting of a container with the aforementioned fliptop closure inside a woman's purse. In this case, with the forces experienced by the purse, or by the pressure of other objects contained therein, a deformation of the closure and an unwanted opening might occur.
Another type of fliptop closure in the prior art has an external lock that is inserted into a grip. The lock is hinged to the side of the lid and the grip is arranged externally on the cap.
In this case, as in other similar situations, the opening occurs by pressing forward the lock as a whole, in the direction of the side of the lid, releasing the lock. This design in particular has no obstacle to being opened by a child, and any movement or pressure that displaces the lock slightly will result in releasing the cap, allowing the contents to be spilled out.
Another aspect to be considered in safety closures is the attachment of the lid to the neck of the container in permanent manner.
The lid with the safety closure has to be attached in the neck of the container and be prevented from removal by unscrewing or any other means, there being commonly used for this purpose a screw combined with a ratchet which prevents turning in the direction of unscrewing. This system is effective, but it makes it necessary to adapt the container, providing it with teeth to cooperate with the ratchet of the lid.
Another inconvenience involves the expense of raw material to make the ratchet on the lid, increasing the cost of production. The quantity of raw material expended for the construction of the ratchet on the lid when thousands of units are involved is substantial, increasing the production cost.